CollectionView How to add a head view

We want to use the head view inside the CollectionView to first register the header view Uicollectionreusableview or inherit the Uicollectionreusableview subclass, The kind type is Uicollectionelementkindsectionheader and requires an identifier, and we define a static string that is statically the line, as follows:

[CollectionView registerclass: [Uicollectionreusableviewclass ] forsupplementaryviewofkind :uicollectionelementkindsectionheader withreuseidentifier:headerviewidentifier ];

A few important points that can not be overlooked is that uicollectionviewflowlayout layout properties need to set the size of the headerreferencesize head, otherwise the head view is not the size of the display;

-(uicollectionreusableview *) CollectionView: (uicollectionview *) CollectionView Viewforsupplementaryelementofkind: (nsstring *) Kind Atindexpath: (nsindexpath *) Indexpath; Method creates a header view view and gives the frame, and then adds it to the Uicollectionreusableview.

The detailed code is as follows

2. <pre name= "code" class="OBJC" >//
4. Homeviewcontroller.m
6. Collection adding a head
8. //
10. Created by the user on 15/10/10.
12. Copyright (c) 2015 user. All rights reserved.
14. //
18. #import "HomeViewController.h"
20. #import "ConstomCell.h"
26. Static NSString *headerviewidentifier = @ "Hederview";
30. @interface Homeviewcontroller () <UICollectionViewDataSource,UICollectionViewDelegate>
34. @property (nonatomic,Strong) Uiimageview *headerimage;
38. @end
42. @implementation Homeviewcontroller
46. -(void) Viewdidload {
48. [Super Viewdidload];
50. //1. Adding CollectionView
52. [self addcollectionview];
56. }
60. -(void) Addcollectionview
62. {
64. uicollectionviewflowlayout *layout=[[uicollectionviewflowlayout Alloc]init];
66. Layout. minimumlinespacing=20; //Set spacing for each line
68. Layout. Itemsize=cgsizemake (100, 100); //Set the size of each cell
70. Layout. Sectioninset=uiedgeinsetsmake (0, 0, 50, 0);
72. Layout. Headerreferencesize=cgsizemake (self. View. Frame. Size. Width, 250); //Set the size of the CollectionView head view
76. Uicollectionview *collectionview=[[uicollectionview alloc]initwithframe:self. View.  Bounds Collectionviewlayout:layout];
78. CollectionView. frame=self. View. Bounds;
80. //Register cell cells
82. [CollectionView registernib:[uinib nibwithnibname:@ "Constomcell" bundle: nil]   Forcellwithreuseidentifier:@ "Cell"];
84. //Register head view
86. [CollectionView Registerclass:[uicollectionreusableview class] Forsupplementaryviewofkind:  Uicollectionelementkindsectionheader Withreuseidentifier:headerviewidentifier];
90. CollectionView. Backgroundcolor=[uicolor Whitecolor];
92. CollectionView. delegate= self;
94. CollectionView. datasource= self;
96. [self. View Addsubview:collectionview];
98. }
102. How many rows #pragma mark returns
104. -(Nsinteger) CollectionView: (uicollectionview *) CollectionView numberofitemsinsection: (NSInteger) Section
106. {
110. return 13;
112. }
114. #pragma cells returned by MARKK
116. -(uicollectionviewcell*) CollectionView: (uicollectionview *) CollectionView Cellforitematindexpath: ( Nsindexpath *) Indexpath
118. {
120. Constomcell *cell=[collectionview dequeuereusablecellwithreuseidentifier:@ "Cell" Forindexpath:  Indexpath];
124. return cell;
126. }
130. Return to head view
132. -(Uicollectionreusableview *) CollectionView: (uicollectionview *) CollectionView Viewforsupplementaryelementofkind: (nsstring *) Kind atindexpath: (nsindexpath *) Indexpath
134. {
136. //If the head view
138. if ([Kind Isequaltostring:uicollectionelementkindsectionheader]) {
140. uicollectionreusableview *header=[collectionview dequeuereusablesupplementaryviewofkind:kind   Withreuseidentifier:headerviewidentifier Forindexpath:indexpath];
142. //Add the contents of the head view
144. [self addcontent];
146. //Head view Add view
148. [Header addsubview:selfheaderimage];
150. return header;
152. }
154. //If the bottom view
156. if ([Kind Isequaltostring:uicollectionelementkindsectionfooter]) {
158. //
160. //    }
162. return Nil;
164. }
166. /*
168. * Add header Content
170. */
172. -(void) addcontent
174. {
176. Uiimageview *headerimage=[[uiimageview Alloc]init];
178. Headerimage. Contentmode=uiviewcontentmodescaleaspectfill;
180. Headerimage. clipstobounds=YES;
182. Headerimage. Frame=cgrectmake (0, 0, self. View. Frame. Size. Width, 250  );
184. Headerimage. Image=[uiimage imagenamed:@ "Mei"];
186. self. headerimage=headerimage;
188. }
194. @end

Final effect

CollectionView How to add a head view